str0="人生苦短,"+"我用Python"
print(str0)

str1="123"*2
print(str1)
print("abc"*2)

str2="qwe"
print(str2*3)

str3="qwertyuiop"
print(str3[1])
print(str3[4])
print(str3[6])
print(str3[0])
print(str3[-1])
print(str3[-5])
print('-----------------------------')

str4='qwert123456'
print(str4[::1]) #qwert123456
print(str4[::-1]) #654321trewq
print(str4[0:]) #qwert123456
print(str4[:-1]) #654321trewq
print(str4[2:8]) #ert123
print(str4[-8:-1]) #rt12345
print(str4[2:-2]) #ert1234
print(str4[3:10:2]) #r135
print('-----------------------------')

str5="ZXCVBNM"
print("Z" in str5) # True
print("c" in str5) # False
print("V" not in str5) # False
print("b" not in str5) # True